> > BTW, filesystem freezing never really worked for mmaped writes under> > ext3 - ext3 would have to implement page_mkwrite() callback for that - so> > if you want to rely on it for suspending, this will be non-trivial.> > At this point the purpose of freezing filesystems is basically to> prevent XFS from deadlocking with hibernation's memory preallocation.> For other filesystems it may or may not make a difference depending on> their implementation of freeze/unfreeze_super(). What's exactly the problem? Memory preallocation enters direct reclaimand that deadlocks in the filesystem?